In a wireless communications technology, a user equipment (User Equipment, UE) is connected to a core network by using a radio access network (Radio Access Network, RAN), and a path between the RAN and the core network is called an IP backhaul network (IP Backhaul).
In a wireless communication process, user data (user data) is sent to the core network through a transport network, a base station (evolved NodeB, eNB) is connected to a mobility management entity (Mobility Management Entity, MME)/serving gateway (Serving Gateway, SGW) by using an S1 interface, and the base station eNB is connected to another base station eNB through an X2 interface. User data on the S1 interface and the X2 interface is borne in an IP transmission path by using the GTP-U protocol. A format of a user plane (User plane) protocol stack is shown in FIG. 1, including a physical layer (layer L1), a data link layer (layer L2), a network layer (IP layer), a User Datagram Protocol (User Datagram Protocol, UDP) layer, a GPRS Tunneling Protocol-User plane (GPRS Tunneling Protocol-User, GTP-U) layer, and user data (user data). In a process of wireless signaling interaction, a system control plane allocates one tunnel endpoint identifier (Tunnel Endpoint Identifier, TEID) to a user. In a process of user data packet forwarding, the allocated TEID is carried in a TEID field of a GTP-U header and is used to uniquely identify a user tunnel in a radio access system.
With the exhaustion of Internet Protocol version 4 (Internet Protocol Version 4, IPv4) addresses, the Internet Protocol version 6 (Internet Protocol Version 6, IPv6) will gradually replace IPv4 in radio access networks, and nodes that use an IPv6 network as an IP backhaul network of a base station are on the rise. For an IPv6 backhaul network, a structure of a wireless user data packet in transmission is as follows:
L1L2IPv6UDPGTP-UUser data
It may be seen that, compared with IPv4, in IPv6, a structure of a packet in transmission does not change essentially, and only an IPv6 header replaces an IPv4 header.
However, compared with an IPv4 backhaul network, an IPv6 backhaul network increases overheads of network transmission, reduces proportion of user payload, and affects average transmission efficiency of service data.